The present invention relates to the field of dynamoelectric machines and, more specifically, to rotor winding series connectors for such machines.
An electrical power generator converts mechanical energy into electrical energy. A typical electrical power generator includes a stator and a rotor that rotates within the stator to thereby generate electricity. The rotor, in turn, is mounted to a shaft that drives the rotor. An exciter may be positioned adjacent the generator to provide current to the generator rotor. The exciter generally includes an exciter stator and an exciter rotor that rotates within the exciter stator. The exciter rotor, in turn, is mounted to the shaft that drives the generator rotor. Together, the generator, shaft, and exciter may be considered as a typical generator apparatus.
An exciter is but one example of a dynamoelectric machine. Rotor windings for such a machine may be metallic bar conductors. During a winding refurbishing operation, new rotor windings are installed into the rotor body and opposing first and second rotor winding ends are connected. Referring, for example to FIG. 5, a prior art connection is shown between the opposing first and second rotor winding ends. More specifically, a plurality of first rotor winding ends 10a-10n are connected to respective second rotor winding ends 11a-11n. The first plurality of rotor winding ends 10a-10n are bent downwardly, and the second corresponding plurality of rotor winding ends 11a-11n are bent upwardly to be adjacent the first plurality of rotor winding ends in pairs. The manual bending of the rotor winding ends 10a-10n, 11a-11n may be tedious and labor intensive.
After each pair of first and second rotor winding ends 10a-10n, 11a-11n are bent to a predetermined position, a joint 14 is brazed between adjacent surface portions. Each brazed joint 14 may need to first cool before connecting successive rotor winding ends. Accordingly, the current approach to making series connections for the winding ends is relatively difficult, time consuming, and expensive.
It is therefore an object of the present invention to provide a connector for efficiently connecting rotor winding ends on a dynamoelectric machine.
This and other objects, features and advantages of the present invention are provided by a rotor winding series connector for connecting rotor winding ends. More specifically, the rotor winding series connector may be for a dynamoelectric machine comprising a rotor and a stator surrounding the rotor. The rotor may comprise rotor windings defining at least one pair of first and second rotor winding ends arranged in spaced relation. The rotor winding series connector may comprise a C-shaped connector body having a medial connector portion and respective first and second end connector portions extending outwardly from the medial connector portion.
First and second end connector brackets may be carried by the respective first and second end connector portions for receiving the respective first and second rotor winding ends. The C-shaped connector body may comprise flexible conductive material arranged in a plurality of stacked layers to facilitate installation. The series connector advantageously eliminates the need to precisely manually bend the winding ends and speeds refurbishing, for example.
The rotor winding series connector may comprise insulating material adjacent outer surface portions of the C-shaped connector body and/or the first and second connector brackets. The C-shaped connector body may comprise copper. Each of the first and second brackets may have an L-shape with a first leg extending outwardly from adjacent portions of the respective first and second end connector portions of the C-shaped connector body, and a second leg extending generally parallel thereto. The winding ends can be readily positioned into the brackets.
For a typical installation, such as a generator exciter, a plurality of pairs of first and second rotor winding ends may be connected by a plurality of rotor winding series connectors. More specifically, pluralities of first and second rotor winding ends may be arranged in respective stacks, and a rotor winding series connector may connect each pair of first and second rotor winding ends. Spacing between successive pairs of the first and second rotor winding ends may progressively increase. Accordingly, successive ones of the plurality of rotor winding series connectors may have respective medial portions having progressively increasing lengths corresponding to the progressively increasing spacings. A respective brazed joint may be provided between each of the C-shaped connector bodies and adjacent portions of each of the first and second rotor winding ends.
A method aspect of the present invention is directed to using the rotor winding series connector to connect, in series, at least one pair of first and second rotor winding ends arranged on the rotor in spaced relation. The method may comprise positioning the respective first and second rotor winding ends into the respective first and second connector brackets to thereby connect the respective first and second rotor winding ends together in series. The method may also comprise selecting the rotor winding series connector so that the medial connector portion has a length corresponding to the space between the rotor winding ends. The method may further comprise brazing a respective joint between the C-shaped connector body and adjacent portions of the first and second rotor winding ends.